MCP7940NT-I

{
  "schema_version": 1,
  "type": "component",
  "slug": "mcp7940nt-i",
  "title": "MCP7940NT-I",
  "brief": "Microchip Real-time Clocks (RTC), SOIC-8. Pinout extracted from the datasheet, KiCad symbol/footprint/3D.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "component",
    "rtc",
    "mcp7940nt-i"
  ],
  "component": {
    "mpn": "MCP7940NT-I",
    "manufacturer": "Microchip",
    "package": "SOIC-8",
    "pin_count": 8,
    "category": "RTC",
    "subcategory": "Real-time Clocks (RTC)",
    "datasheet": "https://datasheet.lcsc.com/datasheet/pdf/5093447976d64b9ab2cb1808413f6a3f.pdf",
    "parts": {
      "symbol": "mcp7940nt-i.kicad_sym",
      "footprint": "mcp7940nt-i.kicad_mod",
      "model_3d": "mcp7940nt-i-etched.glb",
      "model_3d_plain": "mcp7940nt-i.glb",
      "model_3d_step": "mcp7940nt-i-etched.step",
      "model_3d_step_plain": "mcp7940nt-i.step",
      "lbr": "mcp7940nt-i.lbr"
    },
    "distributor_links": {},
    "pins": [
      {
        "number": "1",
        "name": "X1",
        "type": "input",
        "description": "Quartz crystal input / external oscillator input. Connects to one terminal of the 32.768 kHz tuning-fork crystal (optimized for 6-9 pF load capacitance) with its external load capacitor to VSS. Also usable as the external clock input when driving the device from an external oscillator."
      },
      {
        "number": "2",
        "name": "X2",
        "type": "output",
        "description": "Quartz crystal output. Connects to the second terminal of the 32.768 kHz crystal with its external load capacitor to VSS. Leave floating when using an external oscillator driving X1."
      },
      {
        "number": "3",
        "name": "VBAT",
        "type": "power_in",
        "description": "Battery backup supply input, 1.3 V to 5.5 V. Maintains RTCC and SRAM when VCC is lost; typical timekeeping backup current is 925 nA at 3.0 V. Tie to VSS if the battery backup feature is not used."
      },
      {
        "number": "4",
        "name": "VSS",
        "type": "power_in",
        "description": "Device ground (0 V) reference for VCC and VBAT rails and all logic signals."
      },
      {
        "number": "5",
        "name": "SDA",
        "type": "bidirectional",
        "description": "Bidirectional I2C serial data (open-drain). Requires an external pull-up resistor to VCC (typ. 10 kΩ at 100 kHz or 2 kΩ at 400 kHz). Data may change only while SCL is low; changes while SCL is high signal Start/Stop conditions."
      },
      {
        "number": "6",
        "name": "SCL",
        "type": "input",
        "description": "I2C serial clock input from the bus master, used to synchronize data transfer to/from the device. Supports clock rates up to 400 kHz. Schmitt-trigger input with 50 ns spike suppression; requires an external pull-up to VCC."
      },
      {
        "number": "7",
        "name": "MFP",
        "type": "output",
        "description": "Multifunction output (open-drain). Configurable as alarm output on an alarm match, as a selectable-frequency square-wave output, or as a general-purpose output driven by the OUT bit in the CONTROL register. Requires an external pull-up resistor to VCC (typ. 10 kΩ); leave floating if unused. VOL = 0.40 V at IOL = 3.0 mA (VCC = 4.5 V)."
      },
      {
        "number": "8",
        "name": "VCC",
        "type": "power_in",
        "description": "Primary power supply, 1.8 V to 5.5 V. Typical timekeeping current 1.2 uA at 3.3 V; SRAM/RTCC register operating current is 300 uA (read) / 400 uA (write) at VCC = 5.5 V, SCL = 400 kHz. Power-fail switchover to VBAT occurs at VTRIP (1.3-1.7 V)."
      }
    ],
    "provenance": {
      "extractor": "ds2sf",
      "datasheet": {
        "url": "https://datasheet.lcsc.com/datasheet/pdf/5093447976d64b9ab2cb1808413f6a3f.pdf",
        "pages": 56,
        "sha256": "4aafe310fbafe313",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 9,
        "described": 9,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "pin1": {
      "pad": "1",
      "at": [
        -2.475,
        -1.905
      ],
      "corner": "top-left",
      "source": "silk-marker",
      "derived_from": "SOIC-8_3.9x4.9mm_P1.27mm@sha256:074ecb2092b24fa4",
      "mark": "drawn"
    }
  },
  "metadata": {
    "specs": {
      "Manufacturer": "Microchip",
      "Package": "SOIC-8",
      "Category": "RTC",
      "Pins": "9"
    }
  },
  "sections": [
    "hero",
    "viewers",
    "readme",
    "breadcrumbs",
    "info"
  ],
  "discovery_triggers": [
    "mcp7940nt-i"
  ],
  "discovery_pitch": "MCP7940NT-I (Microchip) component page with datasheet-verified CAD.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "mcp7940nt-i.kicad_sym",
    "mcp7940nt-i.kicad_mod",
    "mcp7940nt-i.glb",
    "mcp7940nt-i.step",
    "mcp7940nt-i.lbr",
    "docs/hero.png",
    "docs/mcp7940nt-i-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "mcp7940nt-i-etched.step"
  ],
  "visibility": {
    "public": true
  },
  "variants": [
    {
      "mpn": "MCP7940NT-IMNY",
      "kind": "packaging"
    },
    {
      "mpn": "MCP7940NT-I/MNY",
      "kind": "packaging"
    },
    {
      "mpn": "MCP7940NT-ISN",
      "kind": "packaging"
    },
    {
      "mpn": "MCP7940NT-IMS",
      "kind": "packaging"
    },
    {
      "mpn": "MCP7940NT-IST",
      "kind": "packaging"
    },
    {
      "mpn": "MCP7940NT-IP",
      "kind": "packaging"
    }
  ],
  "updated_at": "2026-09-25T01:26:21.987Z"
}